AGE-RELATED MACULAR DEGENERATION (AMD)

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Age-related macular degeneration (AMD), commonly known as macular degeneration, is a disease of the elderly in which degenerative processes take place in the most sensitive part of the retina. This causes progressive, painless loss of central vision, affecting the ability to see fine detail, drive, read and recognise faces. AMD is one of the leading causes of blindness in the western world.

Age-related macular degeneration (AMD) is a deterioration or breakdown of the eye's macula. The macula is a small area in the retina - the light-sensitive tissue lining the back of the eye. The macula is what allows you to thread a needle or read small print. The macular is the centre of the retina, the light detecting nerve layer at the back of your eye.

Macular degeneration does not make you completely blind, but it may damage your central vision leaving you to rely on your peripheral vision.

Normal Vision

Vision with Age-related Macular Degeneration

Currently there is no cure for AMD. There are treatment options that can slow down its progression, depending on the stage and type of the disease (wet & dry). The earlier the disease is detected, the more likely it is that further vision loss can be prevented. There are 2 types of AMD - dry and wet. These are very different. The initial symptom of Wet AMD is sudden distortion/loss of central vision. In dry AMD, vision loss is gradual.

Dry AMD

Dry AMD is due to a loss or accumulation of pigmentation and debris on the retina. This is the most common form of AMD. Dry AMD is caused by a build up of protein deposits called drusen at the macula. These deposits interfere with the health of the macular and reduce it ability to function. Dry AMD causes a deterioration in central vision over many years, it does not affect vision suddenly. There is no treatment for dry AMD. However, the disease can be slowed down in some patients with high doses of anti-oxidants. There are very specific dose combinations that have been proven to work so make sure that the medication you choose is one recommended by your eye care professional.

Wet AMD

The wet AMD implies that there is a leakage of fluid or blood in the central part of the retina. Any of these symptoms should suggest to a patient that they require careful retinal examination by a retinal specialist.

Wet AMD occurs when a new leaky blood vessel grows through defects in the foundation layers of the retina. These new vessels can bleed and cause distortion or loss of your central vision. Wet AMD comes on suddenly and can damage your retina just as quickly. There is a treatment for Wet AMD that is highly effective but it is important that you start the treatment as soon as possible. Aetiology of AMD is multi-factorial including physiological ageing, genetic, dietary, and environmental factors. Different potential therapies have been tried including dietary/vitamin supplement, laser treatment with or without photosensitising dye, radiotherapy, surgical removal of scar tissue, and recently pharmacological treatment (e.g. anti-VEGF therapy, Avastin, Macugen, and Lucentis).

Ninety percent of severe visual loss from AMD is due to the complication of the wet type of macular degeneration. The latest treatment which has revolutionalised the management of wet AMD is the injection of a special drug called Lucentis into the middle of the eye (vitreous). Unlike previous treatments e.g. laser therapy which tended to slow down/limit the loss of vision, a number of patients who received the Lucentis injection actually noticed an improvement in vision.

The original trial of Lucentis suggested injections every month for 2 years. The latest figures suggest that some patients require at least 5 to 6 injections in order to control the wet AMD, while others require monthly injections. Previously, each injection cost A$2000 for the drug alone. From 1st August, 2007, Lucentis was listed on the PBS in Australia, but only for those cases meeting Medicare criteria.

If you have either type of AMD it is important to stop smoking as this can significantly worsen the disease. Much research is being undertaken in this field and it is likely that over the next decade, there should be more major advances.

Note: This information is general in nature and is not a substitute for specialist medical advice. Have your eyes checked regularly every two years, even if you have not noticed any symptoms or changes.